In this study we propose to evaluate three clinical questions relating to the management of thalassemia: 1. We will evaluate (a) the effect of continuous desferrioxamine therapy on the growth, development and cardiac toxicity of children under the age of 5. We will begin desferrioxamine treatment together with the commencement of transfusion therapy; (b) the effect of continuous desferrioxamine therapy on the evolution of chronic hepatitis; (c) the effect of therapy on thalassemia intermedia. 2. We will evaluate the short and long term effects of prenatal diagnosis on the outcome of pregnancy, on the development of the child and on the incidence of homozygous beta thalassemia in the community. Adequate control groups will be available for both these studies. 3. We will investigate the rate of decline of Hb F levels by chemical determination, immunologic assays, as well as globin chain synthesis analysis. Such information will increase our knowledge of the protective effect of the thalassemia state on malaria.